export function isFunc(func) {
	return typeof func === 'function';
}

export function loadScript(url) {
	const head = document.getElementsByTagName('head')[0];
	const script = document.createElement('script');
	script.type = 'text/javascript';
	return new Promise(function(resolve, reject) {
		if (script.readyState) {
			script.onreadystatechange = function() {
				if (
					this.readyState === 'complete' ||
					script.readyState === 'loaded'
				) {
					script.onreadystatechange = null;
					resolve();
				}
			};
		} else {
			script.onload = function() {
				resolve();
			};
			script.onerror = function() {
				reject(new Error('Failed to load' + url));
			};
		}
		script.src = url;
		head.appendChild(script);
	});
}
